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1.
The specific diagnosis of Poecilobdella hubeiensis sp. nov. is given below. Holotype: length 103 mm. when extended; width at buccal ring, 11mm.; maximum width (ⅩⅤⅡ—ⅩⅩⅠ), 27 mm.; diameter of caudal sucker, 11mm. Paratype: One specimen. Rings 103. Somites Ⅰ, Ⅱ and Ⅲuniannulate; Ⅳ, Ⅴ, ⅩⅩⅤⅠ and ⅩⅩⅤⅡ biannulate; Ⅵ, Ⅶ and ⅩⅩⅤ triannulate; Ⅷ and ⅩⅩⅠⅤ quadrannulale; Ⅸ—ⅩⅩⅢ complete with quinquannulate. Gonopores seperated by five annuli, the male at Ⅺ b5/b6 (31/32) or b6, the female at Ⅻ b5/b6 (36/37) or b6. The anus situated on the ring 103. Colour of dorsum in life yellow-green; that of renter bluegreen; margins  相似文献   

2.
Myostatin, a new member of the TGF-p superfamily, is predominantly expressed in skeletal muscle cells and functions as a negative regulator of skeletal muscle growth in animals. Recently, we have reported three single nucleotide polymorphisms (SNPs) in the chicken my-ostatin gene. Herein, we investigate the association of those SNPs with the production traits in a F2 chicken line derived from Broilers crossing to Silky with the least square analysis. The results show that the BB and AA genotypes are strongly associated with abdominal fat weight (AFW), abdominal fat percentage (AFP), and birth weight (BW) (P < 0.05). Breast muscle percentage (BMP) of the AA type is higher than that of the AB type. The breast muscle weight and breast muscle percentages of F2 individuals have significant difference between CC and DD genotypes (P< 0.05). Breast muscle weight (BMW) of EF birds is higher than that of EE birds (P< 0.05). In this report, we present the first genetic evidence to show that chicken myostatin not o  相似文献   

3.
鹟科五种鸟线粒体DNA序列变化与亲缘关系的研究   总被引:4,自引:1,他引:3  
首次对鹟科(Muscicapidae)画眉亚科三种鸟----画眉(Garrulax canorus)、红嘴相思鸟(Leiothrix lutea)、棕头雅雀(Paradoxornis webbiana);鸫亚科的乌鸫(Turdinae merula)线粒体DNA的12S rRNA基因片段的DNA序列进行了测定,并与北美画眉亚科弯嘴鹛属(Pomatostomus)的灰冠弯嘴鹛(P.temporalis)同源序列进行分析比较并构建分子进化树。实验结果与传统形态学论述存在一定的差异,与同工酶研究结果相同:画眉与红嘴相思鸟的亲缘关系最近,棕头鸦雀较乌鸫与画眉亚科的关系更近,为将其置于画眉亚科提供了分子证据。 Abstract:The classfication on Muscicapinae disturbed us for a long time.The important thing is to find an appropriate character to resolve it.It is the first time that we testified the mitochondrial 12S rRNA gene fragment sequence of four birds (G.canorus,L.lutea,P.webbianus and T.merula-owing to Muscicapinae) and aligned with the same sequence of P.temporalis.Using the mitochondrial 12S rRNA sequences date,we built phylogenetic trees.The results indicated that that the relationship between Garrulax canorus and Leiothrix lutea in the four birds was closer which is congruent with morphology.According to the results of isoenzyme and DNA sequencing data,we can draw a conclusion that Paradoxornis webbianus has closer relationship to Timaliinae than that of Turdus merula,and that putting Paradoxonithinae to Timaliinae was reasonable.  相似文献   

4.
姜海英  陆佩洪  李悦民 《遗传》2000,22(1):21-24
首次对鹟科(Muscicapidae)画眉亚科三种鸟----画眉(Garrulax canorus)、红嘴相思鸟(Leiothrix lutea)、棕头雅雀(Paradoxornis webbiana);鸫亚科的乌鸫(Turdinae merula)线粒体DNA的12S rRNA基因片段的DNA序列进行了测定,并与北美画眉亚科弯嘴鹛属(Pomatostomus)的灰冠弯嘴鹛(P.temporalis)同源序列进行分析比较并构建分子进化树。实验结果与传统形态学论述存在一定的差异,与同工酶研究结果相同:画眉与红嘴相思鸟的亲缘关系最近,棕头鸦雀较乌鸫与画眉亚科的关系更近,为将其置于画眉亚科提供了分子证据。 Abstract:The classfication on Muscicapinae disturbed us for a long time.The important thing is to find an appropriate character to resolve it.It is the first time that we testified the mitochondrial 12S rRNA gene fragment sequence of four birds (G.canorus,L.lutea,P.webbianus and T.merula-owing to Muscicapinae) and aligned with the same sequence of P.temporalis.Using the mitochondrial 12S rRNA sequences date,we built phylogenetic trees.The results indicated that that the relationship between Garrulax canorus and Leiothrix lutea in the four birds was closer which is congruent with morphology.According to the results of isoenzyme and DNA sequencing data,we can draw a conclusion that Paradoxornis webbianus has closer relationship to Timaliinae than that of Turdus merula,and that putting Paradoxonithinae to Timaliinae was reasonable.  相似文献   

5.
The authors have done some researches on the leaves and stems of potamogeton L. in Inner Mongolia by comparative classification by using the methods of morphology and anatomy. After having studied we found that they are ten species in Inner Mongolia. Among them, five species are belonged to cosmopolitans P. perfoliatus L., P. crispus L., P. pectinatus L., P. panormitanus Biv. and P. lucens L.; two eastern Asian sppcies: P. distinctus A. Benn. ao(?) P. malaianus Miq.; P. vaseyi Robbins is an East Asian-North American species) P. zosterifolius Schum. is an Eurasian species; one new species, P. acifolius Ma, is endemic to lnner Mongolia.  相似文献   

6.
光周期诱导红腹锦鸡冬季繁殖效果初报   总被引:6,自引:0,他引:6  
?College of Life Science, Hebei Normal University, Shijiazhuang 050016, China)Golden pheasant ( Chrysolophus pictus) is a monotypic and special species of China.In nature, it breeds once a year in spring summer.From Oct.1998 to Feb.1999, we studied the effects of photo periods on inducing the birds to reproduce in winter and succeeded.In the experiment, 36 adult females and 18 males were divided into three groups.Each group was divided into 6 replicates, each replicate included 2 females and 1 male, and fed in one cage.All the groups were exposed to short day (8L∶16D) for 8 weeks, and then transferred to long day (12L∶12D, 14L∶10D or 16L∶8D). In result, photoperiods significantly affected Golden pheasant reproductive performance in winter.Considered of all of the reproductive performance indicators, the reproductive performance of the group exposure to 14L∶10D was the best, the 16L∶8D group's was less and the 12L∶12D group's was the worst.It may be that the birds' CDL (critical day length) for inducing egg production was about 12 h, and the CDL for optimal egg production was 14L∶10D in winter. The birds exposed to 12L∶12D had no fertilized egg.The other groups had fertilized eggs and the fertility was 15 05% (14L∶10D) and 20 41% (16L∶8D).The hatchability of fertilized egg were 76 47% (14L∶10D) and 80 00% (16L∶8D). The egg laying pattern was affected by the size of photoperiod.The ratio of lay of the birds exposed to 14L∶10D, increased rapidly and sustained in a peak level for 5 weeks, and then fall down.But the other birds (group A and C) increased to the peak at the first week and then fall down quickly.  相似文献   

7.
The specimens dealt with here were furnished by Prof.K.C.Yang and Miss W.S.Wu in 1961 to the writer for study.They were collected from the lower part of theShizixu formation of Luocheng and Huanjiang districts,Kwangsi province and from thelower part of the Kolaoho formation of Dushan and Duyun districts,southern Kuei-chow province.All the stromatoporoids obtained from Kwangsi are associated with coral:Cystophrentis sp.;and those from Kueichow are associated with brachiopods:Schucher-tella sp.,Athyris sp.,Camarotoechia sp.,a little bit below the horizon of Cystophrentis.  相似文献   

8.
In this article, RAPD was employed to detect the DNA polymorphism of Carchesium polypinum in three lakes: Nanhu Lake (N), Shahu Lake (S) and Donghu Lake (D). The results were used to deduce the definition of the populations: (1) The 20 primers produced 172 clear bands with an average of 8.6 fragments ranging from 100bp to 1600bp. The other 11 primers produced 59 legible bands with an average of 5.4 fragments ranging from 100bp to 1 500bp; (2) SPSS 12.0 and RAPDistance 1.04 that had similar trees were composed of two parallel main branches. Samples from Shijizhong (Z) of D, Shuiguohu (H) of D and N clustered into a branch and another sample from D — Fengguangcun (F) — gathered with S or made another main branch itself. The result that the three samples from D were separated by the samples from other lakes suggested that the individuals of C. polypinum in D belong to several populations. This discovery will promote micro-hydrobiont population ecology research. In addition, it will help in the study of the essence of the transitional zone and its dispersal and vicariance behavior. We believe that this study will contribute to the study of population differentiation and the mechanism of speciation.  相似文献   

9.
In recent studies, some progress has been made in the vocal mechanism of songbird by using both electrophysiological and acoustics technique[1—3]. High vocal center (HVC) is the highest center in the vocal control pathway in songbirds. Unilateral stimulating HVC may evoke bilateral electrical activity of HVC neurons[4,5]. The lesion of HVC critically affects the capacity of singing, and birds could produce only simple calls. In addition, the basic frequency decreases, rapid modulation o…  相似文献   

10.
Food resources play an important role in the regulation of animals’ physiology and behavior. We investigated the effect of short-term food restriction on metabolic thermogenesis of Chinese bulbuls(Pycnonotus sinensis) by measuring changes in body mass, body fat, basic metabolic rate(BMR), and organ mass of wild-caught Chinese bulbuls from Wenzhou, China. Short-term food restriction induced a significant decrease in body mass and body fat but body mass returned to normal levels soon after food was no longer restricted. Food restriction caused a significant reduction in BMR after 7 days(P<0.05), which returned to normal levels after food restriction ceased. Log total BMR was positively correlated with log body mass(r2=0.126, P<0.05). The dry masses of livers and the digestive tract were higher in birds that had been subject to temporary food restriction than in control birds and those subject to continual food restriction(P<0.001 and P<0.05, respectively). There was also significant differences in the dry mass of the lungs(P<0.05), heart(P<0.01), and spleen(P<0.05) in birds subject to short-term food restriction compared to control birds and those subject to continual food restriction. BMR was positively correlated with body and organ(heart, kidney and stomach) mass. These results suggest that the Chinese bulbul adjusts to restricted food availability by utilizing its energy reserves, lowering its BMR and changing the weight of various internal organs so as to balance total energy requirements. These may all be survival strategies that allow birds to cope with unpredictable variation in food abundance.  相似文献   

11.
The effects of intercropping of wheat cultivars and oilseed rape on the densities of wheat aphid, Sitobion avenae, and their arthropod natural enemies were evaluated. Three winter wheat cultivars with different resistant levels to S. avenae were used: ‘KOK’ (high resistance), ‘Xiaobaidongmai’ (low resistance) and ‘Hongmanghong’ (susceptible). The results showed that the densities of S. avenae were significantly higher on the monoculture pattern than on either the 8-2 intercropping pattern (eight rows of wheat with two rows of oilseed rape) or the 8-4 intercropping pattern (eight rows of wheat with four rows of oilseed rape). The mean number of predators and the mummy rates of S. avenae were significantly higher in two intercropping patterns than those in the monoculture pattern. The densities of S. avenae, ladybeetles, and mummy rate of S. avenae were significantly different among different wheat cultivars. The highest densities of S. avenae and ladybeetles were found on wheat cultivar Hongmanghong. The lowest densities of S. avenae associated with high mummy rate of S. avenae were found on wheat cultivar Xiaobaidongmai. The results showed that wheat-oilseed rape intercropping conserved more predators and parasitoids than in wheat monoculture fields, and partial resistance of wheat cultivar Xiaobaidongmai had complementary or even synergistic effects on parasitoid of S. avenae.  相似文献   

12.
Wang W L  Liu Y  Chen J L  Ji X L  Zhou H B  Wang G 《农业工程》2009,29(3):186-191
The effects of intercropping of wheat cultivars and oilseed rape on the densities of wheat aphid, Sitobion avenae, and their arthropod natural enemies were evaluated. Three winter wheat cultivars with different resistant levels to S. avenae were used: ‘KOK’ (high resistance), ‘Xiaobaidongmai’ (low resistance) and ‘Hongmanghong’ (susceptible). The results showed that the densities of S. avenae were significantly higher on the monoculture pattern than on either the 8-2 intercropping pattern (eight rows of wheat with two rows of oilseed rape) or the 8-4 intercropping pattern (eight rows of wheat with four rows of oilseed rape). The mean number of predators and the mummy rates of S. avenae were significantly higher in two intercropping patterns than those in the monoculture pattern. The densities of S. avenae, ladybeetles, and mummy rate of S. avenae were significantly different among different wheat cultivars. The highest densities of S. avenae and ladybeetles were found on wheat cultivar Hongmanghong. The lowest densities of S. avenae associated with high mummy rate of S. avenae were found on wheat cultivar Xiaobaidongmai. The results showed that wheat-oilseed rape intercropping conserved more predators and parasitoids than in wheat monoculture fields, and partial resistance of wheat cultivar Xiaobaidongmai had complementary or even synergistic effects on parasitoid of S. avenae.  相似文献   

13.
Wang A Q  Yu Y H  Zhang W J  Gong Y C 《农业工程》2006,26(3):895-900
In this article, RAPD was employed to detect the DNA polymorphism of Carchesium polypinum in three lakes: Nanhu Lake (N), Shahu Lake (S) and Donghu Lake (D). The results were used to deduce the definition of the populations: (1) The 20 primers produced 172 clear bands with an average of 8.6 fragments ranging from 100bp to 1600bp. The other 11 primers produced 59 legible bands with an average of 5.4 fragments ranging from 100bp to 1 500bp; (2) SPSS 12.0 and RAPDistance 1.04 that had similar trees were composed of two parallel main branches. Samples from Shijizhong (Z) of D, Shuiguohu (H) of D and N clustered into a branch and another sample from D — Fengguangcun (F) — gathered with S or made another main branch itself. The result that the three samples from D were separated by the samples from other lakes suggested that the individuals of C. polypinum in D belong to several populations. This discovery will promote micro-hydrobiont population ecology research. In addition, it will help in the study of the essence of the transitional zone and its dispersal and vicariance behavior. We believe that this study will contribute to the study of population differentiation and the mechanism of speciation.  相似文献   

14.
鸟类线粒体DNA研究概述   总被引:8,自引:0,他引:8  
陈晓芳  李爽  王黎  袁晓东  汤敏谦  李庆伟 《遗传》2002,24(3):371-375
线粒体DNA作为理想的分子标记已被广泛用于鸟类种群遗传学和进化遗传学的研究,并取得了许多有意义的结果。本文介绍鸟类线粒体DNA的组成、结构特点及多态性的研究,综述近年来有关鸟类分子进化研究的进展情况,对今后的发展进行了初步的探讨。 Abstract:Mitochondrial DNA as a genetic marker has been successfully applied to the study of molecular evolution of birds.The apparently maternal inheritance of mitochondrial DNA and its fast evolution in primary sequence has made it attractive in population and evolutionary genetics.Mitochondrial DNA of birds displays two characteristics not seen in other vertebrates mtDNA,that is,a novel gene order and the absence of an equivalent to the light-strand replication origin.The research on polymorphism of mtDNA can resolve phylogenies of birds both at lower and higher taxonomic levels.Here we review progress on avian molecular evolution in recent years,and make preliminary studies of the development in this field.  相似文献   

15.
Lin X Z  Gao A G  Chen H W 《农业工程》2008,28(12):6364-6370
Isolation, molecular identification and phylogenetic analysis were carried out to investigate the biodiversity of manganese bacteria in sediments which were collected from the Arctic Ocean during the 2nd Chinese Arctic Scientific Expedition. 21 and 19 species of cultivable strains were isolated from sediments at Stations P11 and S11, respectively, according to their distinct morphological character on the screening plate of manganese medium. Molecular identification and phylogenetic analysis showed that the cultivable manganese bacteria from Station P11 were basically composed of γ-Proteobacteria (γ subgroup of the Proteobacteria branch of the domain Bacteria) and Actinobacteria, which accounted for 86% and 14%, respectively. The isolates of γ-Proteobacteria mainly included Psychrobacter, Shewanella, Acinetobacter and Marinobacter, of which Psychrobacter was the major genus, which accounted for 67% of the γ-Proteobacteria. The cultivable manganese bacteria from Station S11 included α-Proteobacteria, γ-Proteobacteria and Flavobacteria of Bacteroides. The γ-Proteobacteria mainly included Shewanella, Marinomonas and Alteromonas. The majority of α-Proteobacteria was Sphingomonas. The phylogenetic analysis indicated that bacteria from sediments at Stations P11 and S11 had different cultivable manganese microbial communities. All tested strains had higher resistance to Mn2+, of which Marinomonas sp. S11-S-4 had the highest resistant ability.  相似文献   

16.
The fusulinids herein described and figured were collected by Mr.Q.S.Yang andhis colleagues in recent years from several localities in the Dongfang district of the westernpart of Hainan Island,Kwangtung Province.The fusulinid-bearing beds in this region arefractured by numerous faults into discontinuous outcrops.The generalized stratigraphicsuccession of these beds and their underlying and overlying formations,according toMessrs.Q.S.Yang and Q.Q.Wu(1964),are as follows(in descending order):  相似文献   

17.
A novel Clade 2.3.2.1c H5N1 reassortant virus caused several outbreaks in wild birds in some regions of China from late 2014 to 2015.Based on the genetic and phylogenetic analyses,the viruses possess a stable gene constellation with a Clade 2.3.2.1c HA,a H9N2-derived PB2 gene and the other six genes of Asian H5N1-origin.The Clade 2.3.2.1c H5N1 reassortants displayed a high genetic relationship to a human H5N1 strain(A/Alberta/01/2014).Further analysis showed that similar viruses have been circulating in wild birds in China,Russia,Dubai(Western Asia),Bulgaria and Romania(Europe),as well as domestic poultry in some regions of Africa.The affected areas include the Central Asian,East Asian-Australasian,West Asian-East African,and Black Sea/Mediterranean flyways.These results show that the novel Clade 2.3.2.1c reassortant viruses are circulating worldwide and may have gained a selective advantage in migratory birds,thus posing a serious threat to wild birds and potentially humans.  相似文献   

18.
新疆赖草属二新种   总被引:5,自引:1,他引:4  
吴玉虎 《植物研究》1992,12(4):343-347
本文发表了我们在编写《flora of kunlun and karakorum》(禾本科)时发现的两个新种:若羌赖草Leymus ruoqiangensis S.L.Lu etY.H.Wu,sp.nov.;皮山赖草Leymus pishanica S.L.Lu et Y.H.Wu,sp.nov.  相似文献   

19.
西藏色季拉山暗针叶林凋落物层化学性质研究   总被引:9,自引:1,他引:9  
The storage and chemical properties of the forest litter in dark coniferous forest of Sejila Mountain were studied. The results showed that the existing storage was 5. 863t·hm^-2 and the annual litter fall was 0. 3205 t·hm^-2 It implied that the forest litter decomposed slowly and accumulated quickly, and the turnover of nutrient circles was slow. The contents of N, Ca, Na, and Mn nutrient elements in litter layer were in the order of un-decomposed layer (U layer) > semi-decomposed layer (S layer) > decomposed layer (D layer), those of K, Fe, and Mg were in the order of D layer > S layer > U layer, and P element content was in the order of U layer > D layer> S layer. The pool of elements was 78. 483 kg·hm^-2 N, 3. 843 kg·hm^-2P, 48. 205 kg·hm^-2 K, 23.115 kg·hm^-2 Ca, 13. 157 kg·hm^-2 Na, 30.554 kg·hm^-2 Fe, 2. 113 kg·hm^-2 Mn and 27. 513 kg·hm^-2 Mg. The turnover of forest litter was the total of nutrient release accumulation. K, Fe, and Mg were enriched, and N,Ca, Na, Mn, and P were released with the turnover rate in the order of N > Ca > Na > Mn >P.  相似文献   

20.
Two Na^+ and Cl^- Hyperaccumulators of the Chenopodiaceae   总被引:1,自引:0,他引:1  
The authors found five sodium (Na^ ) and chloride (Cl^-) hyperaccumulating halophytes in the Temperate Desert of Xinjiang, China and studied two of them (Suaeda salsa (L.) Pall. and Kalidium folium (Pall.) Moq.). K. folium and S. salsa had a NaCl content of 32.1% and 29.8%, respectively, on a dry weight basis. X-ray microanalysis of the Na in the vacuole, apoplasts and cytoplasm of the two plants indicated a ratio of 7.3:5.6:1.0 in K. folium and 7.3:6.6:1.0 in S. salsa. These data show that K. folium and S. salsa both have a high Na and Cl^- accumulating capacity, which is related to high activity of tonoplast H^ -ATPase and H^ -PPase.  相似文献   

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